All language subtitles for The.UnXplained.Special.Presentation.S02E07.1080p.WEB.h264-EDITH_track3_[eng]

WILLIAM SHATNER:
An opulent island nation
destroyed by the gods.

Stone tablets that point to

a complex in
the middle of the ocean.

And massive rock monoliths
that may reveal

a lost civilization.

It's remarkable to be living
in the 21st century

and to be surrounded
by the ruins

of ancient civilizations.
And all around us

are the remnants
of great cultures

who, for thousands of years,

created
sophisticated communities

and complex societies.

The history of our ancestors
is still a puzzle

we try to solve
by piecing together

written records
and stone monuments

and buried artifacts.

What secrets might be uncovered

hidden beneath our feet and in
the depths of our watery oceans?

Well, that is what
we'll try and find out.

♪ ♪

Within this modern city
stands the ruins

of a citadel that was once
the center of Ancient Greece.

The Ancient Greek
civilization lasted

for more than three centuries.

The Greeks developed
a sophisticated culture,

which had a profound impact
on Western politics,

science and philosophy.

One of the best known
Greek philosophers was Plato,

who wrote more than 20
important philosophical texts

known as "dialogues."

RIC RADER:
Plato was doing
his major writing

in the fourth century BCE,

and Plato's works
are very serious,

very sober
philosophical reflections

on major, major questions.

He is really
the most important philosopher

in the Western world.

RICHARD FREUND:
For most of Western
civilization, Plato is the basis

for our thinking
and philosophy,

but he's also
partially historian.

And his work is still used

in order to identify
the way life was in antiquity.

SHATNER:
Of all the influential
writings of Plato,

the one that is perhaps
the most fascinating

and the most mysterious

is his account of
a lost civilization that existed

centuries before
the rise of Ancient Greece.

Atlantis.

Atlantis is a very important
story in Western imagination.

In the year 359,
before the Common Era,

Plato, the great philosopher,
told a story

about a continent,
a large island

out in the Atlantic Ocean.

And it became
a very powerful nation.

It was home
to a fabulous civilization

that began as the byword
for justice and compassion.

It had a huge navy
that it used to travel

from place to place
around the Mediterranean.

ANDREW COLLINS:
Plato tells us in his dialogues
that the information came from

a famous statesman
who visited Egypt

by the name of Solon,
a few centuries before.

SHATNER:
Plato wrote that Solon
traveled to northern Egypt,

and entered a sacred temple

dedicated to the Egyptian
goddess Neith.

Within the temple was a column

completely covered
with hieroglyphics,

on which the history
of Atlantis was recorded.

Egyptian priests told Solon

the story
of this lost civilization,

which predated
the Egyptians themselves.

Egyptians would recount
the story of Atlantis

as a major, major part of where
their civilization came from,

where they got
a lot of their knowledge.

This was a very advanced
and technological civilization

and Plato was
reporting this as a very,

very important story
for the ancient Egyptians.

Pretty much, like, the next
day after Plato writes this,

people start debating
whether or not it was true.

Did Plato mean this
as a fictional story

or was Plato talking about
a historical occurrence?

SHATNER:
While it may sound like
the stuff of fantasy,

in his dialogues
Timaeus and Critias,

Plato provides a wealth of
detail about what many believe

was a very real island nation.

HUGH NEWMAN:
Plato described Atlantis
as being a huge landmass,

potentially
in the Atlantic Ocean.

One of the main design specs
of Atlantis was this huge area

at the center of
the main city of Atlantis

that had concentric circles
of land and canals.

It had a canal coming out
that went to the sea and

a great port was built there.

YOUNG:
The concentric circles
of navigable canals suggest

a well-planned early marina.

It is strongly oriented
to the sea.

In the temple, on the acropolis
at the center of Atlantis

there is a statue of Poseidon,
the creator god of the place.

And he's got winged horses,

a chariot with horses
that can fly.

So, there is also a transcendent
dimension implied.

SHATNER:
But if such a transcendent,
awe-inspiring place

actually existed,
what happened to it?

According to Plato,
the Atlanteans angered the gods

with their pride--
what the Greeks called "hubris."

And you definitely
don't want to do that.

YOUNG:
Atlantis got more and more vain,

more and more abusive
in their hubris,

a kind of arrogance
that was saying, "We are gods."

That vanity of thinking
that we are as important

as the gods
tends to upset the gods

and then the downfall comes,
the downfall that

is in every Greek tragic play
is the same thing.

People of great privilege
are brought down.

Atlantis disappeared
in a day and a night

due to some natural catastrophe,
and it ended up under the waves.

YOUNG:
The gods came and destroyed
the whole place.

The people were killed, the navy
was destroyed, all in a day.

And Atlantis sinks into the sea.

When Plato talks about
this catastrophic destruction

of Atlantis,
I have to take him seriously.

And people would say, "Oh,
it's just a metaphor, Atlantis."

Every metaphor has at its base

a nucleus of
historical information.

So even if he fictionalized it,
even if he elaborated it,

at its nucleus,
it's a real historical place.

SHATNER:
Obviously, the best way to prove
whether or not Atlantis exists

is to find it.

And rediscovering
mythological cities

isn't as far-fetched
as it might sound.

Other than the myth of Atlantis,
the other great myth

was the existence of Troy...

...a city that rivaled
the Greeks in power.

We know about the Trojan horse.

We know about Helen of Troy.
We know about Achilles.

SHATNER:
For centuries, scholars
scoffed at the notion

that Troy was a real place.

That is, until
amateur archaeologist

Heinrich Schliemann
went looking for it in 1871.

And believe it or not,
Schliemann found Troy,

pretty much where
Homer said it would be.

KAKU:
And that spawned
a whole industry

of trying to find
other ancient cities.

But I think it also raised
false hopes

that we would find Atlantis

the same way we found
the city of Troy.

It may not be so easy.

SHATNER:
The modern search for Atlantis
was kicked off

back in the late 19th century
by a rather curious

amateur scientist
named Ignatius Donnelly.

CHRISTOPHER BADER:
Ignatius Donnelly
wrote a book called

Atlantis: The Antediluvian World

back in 1882.

And this was a book
that really brought Atlantis

out of Plato's fables
and into modern consciousness.

He said Atlantis really existed,

really did
have advanced technology.

SHATNER:
For Donnelly, researching
the story of Atlantis

became such an obsession

that he even went so far as
to claim that he knew precisely

where Atlantis
would one day be found.

YOUNG:
Ignatius Donnelly said
Atlantis was in

a very specific place
in the Atlantic Ocean,

that it sank
and that the Azores--

the islands out there
off Spain--

are the tips of the mountains.

Now we have good
undersea exploration.

We can go down and see
the heavy silt

that is at the ocean bottom
that took

millions of years to build up.

It couldn't have been
a civilization

that sank
a few thousand years ago.

So he was wrong.

But Ignatius Donnelly
advanced the idea

that Atlantis may have
physical history to it.

SHATNER:
Many researchers
believe that the best way

to find Atlantis
is to look for it

where Plato said it was located.

FREUND:
Plato gives us very specific
geographic locations

for where Atlantis was.

He says it's by
the Pillars of Hercules.

And the pillars were
actually two mountains,

one located at
the Rock of Gibraltar

and the other
located in Morocco.

And these two rocks
were the Pillars of Hercules.

So, he's putting it in
a very specific location

that every single reader
knew about.

SHATNER:
Do the ruins of
the legendary city of Atlantis

lie deep beneath
the Mediterranean Sea?

It's an intriguing thought,

and not completely outside
the realm of possibility

when you consider
the mystery surrounding

an abandoned tropical complex
that may be the home of

the lost continent of Mu.

SHATNER:
A team of geologists
at GNS Science

announce a major discovery

related to
the Earth's continents,

the vast landmasses that
make up the planet's surface.

The scientists found that, in
addition to the seven continents

that humans have
known about for centuries,

there's also an eighth
continent located directly

underneath New Zealand,
which they named Zealandia.

Zealandia sank into the ocean

approximately
50 million years ago,

and its existence suggests
that there may be

even more lost continents that
were swallowed up by the sea.

The Earth has cycles
of sea level rise

and sea level fall.

Over the last
hundreds of millions of years,

as climate has warmed,
we get sea level rise.

Cold periods, sea level fall.

There's a huge amount of land
which is now covered by the sea.

Ten thousand years ago,
with the end of the Ice Age,

sea levels were dramatically
lower than they are now.

And because of
the melting of the ice,

sea levels have risen since then

and cities that may have existed
thousands of years ago

could be lost in history
as a consequence.

SHATNER:
For thousands of years,
cultures from around the world

have told stories
about long-lost continents

that were home
to human civilizations

and are now submerged
beneath the waves.

Perhaps the most famous
is the legend of Atlantis,

a massive island that was home
to an advanced civilization,

before it supposedly sank into
the ocean after an earthquake.

NEWMAN:
There's been more books
written about Atlantis than

any other lost continent
in history.

There are many sunken cities,
lost lands,

destroyed continents,
all around the planet

in legend and history.

For example, we have
the lost land of Hy Brasil,

which was thought to be 200
miles off the coast of Ireland.

And it was even on maps
until the 1800s.

SHATNER:
One of the most
intriguing lost continents

is a landmass that is believed

to have once existed
in the Pacific Ocean.

A mythical land
that is known as Mu.

The first person
to write extensively

about the lost continent of Mu

was a Scottish writer

by the name of James Churchward.

In the 19th century,
he was in India

when he visited a monastery.

And the monks there
had records, apparently,

tablets that referred
to this place called Mu

that was this huge continent
that supposedly existed

from Hawaii in the north

down to Easter Island
in the southeast,

right the way across
to Micronesia in the west.

And the people there were
supposedly called the Naacal.

The continent of Mu thrived

perhaps 50,000 years ago

and was sunk beneath the waves,

possibly at the end
of the last ice age.

My great-grandfather,
James Churchward--

eventually, he became friends
with the rishi of the temple

that he visited in India.

And the rishi
mentioned that he was

a member
of the Naacal brotherhood,

the holders of
wisdom and knowledge

of the lost continent of Mu.

They were mighty navigators
and sailors

and established civilization
in other parts of the world.

SHATNER:
According to James Churchward,

the Naacal civilization
had a population

of more than 60 million people
at its peak,

before a massive
volcanic cataclysm

caused Mu to vanish
beneath the waters.

So far, no evidence
of the lost continent

has been found
on the ocean floor.

But some researchers
claim that, incredibly,

a tiny remnant of Mu may still
exist above water today

on an island located

in a remote part
of the Pacific Ocean.

Roughly 2,500 miles
northeast of Australia

lie the ruins of a once great
ancient city: Nan Madol.

Nan Madol is a complex
of man-made islands

built with massive stone blocks

that float atop
a submerged coral reef.

COLLINS:
So, as you approach Nan Madol,

there are a series of islands,

and they're built
actually on coral,

the only place in the world
where this actually occurs.

And you've got all
these incredible structures

made of these prismatic blocks.

At Nan Madol, you have
these ridiculous basalt columns.

They're huge, some of them,
up to, like, 40 tons,

even more, in some cases.

Some of them are raised
very high up in the air,

on the very top levels.

So there's a real problem
when it comes to

try and understand
how they moved

these millions of tons
of basalt columns.

One of the biggest mysteries
surrounding Nan Madol

is that nobody really knows
who constructed it.

But there's some very
strange stories about

how the city
came into existence.

For instance,
one of the stories talks about

it being constructed by
so-called master builders

turning up
and using a magical force

to raise the blocks into
the air and put them into place,

almost as if they could
levitate these blocks.

Some people actually
suggested that maybe Nan Madol

was the last remnant of Mu

that was still above water,

and it was simply indicative of

what had sunk beneath the waves

from this advanced civilization.

Nan Madol is in Micronesia,

so it fit
the correct general area.

And this is one reason
people thought in terms of Mu.

NEWMAN:
When it comes to looking
for this lost continent of Mu,

places like Nan Madol
really do suggest

there could be much more
down there than we realize

on the bottom of the ocean.

SHATNER:
It's exciting to think
that the study of Nan Madol

could one day shed light

on who built these
extraordinary structures

and where they may have
disappeared to.

Such is the case a half
a world away in Sardinia,

where elaborate carvings,

strange statues
and massive tombs

may soon reveal the identity
of an ancient race

of giants.

SHATNER:
On this island
located off the coast of Italy,

a farmer in a region
known as Mont'e Prama

is tilling his fields
when he strikes

what appears to be a large rock.

But upon closer inspection,
he realizes that his plow

has revealed something
far more amazing.

It's the head of a massive,
ancient statue.

The farmer started
digging around it,

brushing away the mud,
pulled it out,

and there was this giant
stone head gazing back at him

with these obsidian eyes.

And so this became
quite a sensation at the time.

It was one of the most important

archaeological discoveries
of the decade.

EDWIN BARNHART:
Subsequently, archaeologists
entered the area,

and through the late 70s,

they dug and they found
over 5,000 fragments

of these giant statues.

We have archers, we have
warriors, we have boxers.

They are, generally speaking,
about eight feet tall,

and approach a ton in weight.

And they are unique
in the regard

that for their time, there was

no other statuary that was
in human form and size

and that level of detail
and sophistication.

SHATNER:
The monolithic statues
came to be known

as the Giants of Mont'e Prama.

According to archaeologists,
they were carved by

the Nuragic people,
a mysterious civilization

that lived on Sardinia
nearly 4,000 years ago.

The Nuragic people were
the indigenous population

of Sardinia,
beginning around 1750 BCE.

And they were not the kind of
society that would have writing.

So, we don't know a lot
beyond their everyday lifestyle,

which would be, in many ways,
similar to what was going on

throughout the Mediterranean
at the same time.

SHATNER:
Incredibly, some researchers
claim that the reason

why the Nuragic people
carved statues

that were eight feet tall

is because these monoliths

were created in the image

of an actual race of giants.

NEWMAN:
One of the strange things
about these statues

is that they appear
to be buried

underneath these
kind of slabs of stone

in this elongated grave,
as though they were

almost like ancestors
being buried in the ground.

Why they did this,
we don't know.

But there are
many legends of giants

all over Sardinia and
the stories go on and on and on.

So, these could be
the same giants who were

memorialized
in these particular statues.

SHATNER:
Could the monoliths of
Mont'e Prama really be evidence

that a civilization of giants

once inhabited the island
of Sardinia, as some believe?

Many researchers
think that it's possible,

and claim that there
are additional clues in folklore

throughout the Mediterranean.

LaCROIX:
Diodorus, an ancient
Greek historian,

discussed how there
was an ancient bloodline

of the Athenian civilization

known as the 50 sons of Hercules
that mated

with a mortal race of women
to create a giant bloodline

that built these
monolithic statues

on the island of Sardinia.

NEWMAN:
This story really put the idea

into different
philosopher's heads that

this was actually
a very advanced culture

that kind of led up to the time
of the Nuragic people

and culminated in the era
of the Mont'e Prama giants.

SHATNER:
The massive monoliths
of Mont'e Prama

and stories from folklore aren't
the only pieces of evidence

to suggest that giants
once lived on Sardinia.

Because there are
also mysterious tombs

located throughout the island
that may have been

where their oversized bodies
were buried.

TYKOT:
What we see at Mont'e Prama

are totally separate structures

for where they
buried their deceased,

and these are called the giants'
tombs, tomba dei giganti.

They are typically
made of one very large stone

that have a semi-hemispherical

entry area or front

that curves inward

with the center part having
a small hole down at the bottom,

which is where the skeleton
would have been interred.

NEWMAN:
As you see these giants' tombs,
what you realize is

that it's entirely
made of large blocks

with a small opening
in the base.

In tradition,
these were the burial places

designed for giants,
and they would actually

build a tomb around it.

This is one of the clues

that kind of links
with the legends

that giants did exist
in Sardinia.

But there is further evidence
that actual skeletons

have been found in
some of these giants' graves.

We have accounts, from 1901,

where there's a report of four
nine-foot skeletons

being unearthed in the vicinity
in northern Sardinia.

And even relatively recently,

there are reports of
three skeletons being dug up

in an area called Torralba,
in southwest Sardinia.

However, the problem is
is that most of the evidence

has now disappeared.

They've just gone missing,
basically.

And so, you have to question,
why is this?

Is there a cover-up?

SHATNER:
Is it possible that
the bones of giants

have actually been hidden
from the public?

It's an intriguing theory,

and it deepens the mystery
surrounding

the strange, towering statues
uncovered at Mont'e Prama.

BARNHART:
The Giants of Mont'e Prama

are very unique and enigmatic,

and Sardinia's myths and stories

about who these people were
typically talk about giants.

But there's a lot of things
we don't know

about who these people were.

And so, these giant statues

are the mystery
within that mystery.

Are the tombs discovered
on the island of Sardinia

the final resting place
of actual giants?

While some may be wary
of such a conclusion,

our ancestors certainly
went to great lengths

to carve and construct
massive structures out of stone.

Like in the case of a remote
island in the Pacific Ocean

whose picturesque landscape
is covered

with mysterious
colossal monoliths.

SHATNER:
2,300 miles
off the coast of Chile,

an island rises from
the waters of the Pacific Ocean.

Called Rapa Nui by the locals,

the island is perhaps better
known by the name given to it

by Dutch explorer
Jacob Roggeveen

when he landed here
on Easter Sunday,

April 5th, 1722

and dubbed it Easter Island.

Today, some 5,000 people
make their home here,

most of whom are the descendants

of Easter Island's
original inhabitants,

who were also
named the Rapa Nui.

But its most famous residents
are the hundreds of massive,

ancient monolithic statues
known as moai

that are scattered
across its grassy cliffs.

Easter Island is famous
for its moai statues.

They are these human depictions.

Their faces are very long
and their chins are long

and there are over
900 of them on the island.

About 95% of them
were quarried at a crater

called Rano Raraku,

and there are a number

of failed or just
"given up on" moai

still carved into
the crater's face.

The moai vary quite a bit
in size, but the average moai

is about 12 to 13 tons
and about 13 feet tall.

So, people are
really fascinated by this,

and continue
to beg for an explanation

of why did the ancient islanders

in this remote location
invest so much

in these giant statues,
and why are they here?

SHATNER:
Archaeologists estimate
that the moai

were created between
1400 and 1600 AD.

For centuries, experts
have been confounded

as to what these
massive headstones

were intended to represent.

But then, in 2010,
archaeologists uncovered

an important clue when
a series of excavations revealed

that there was more to
the moai than meets the eye.

SCHOCH: They discovered
the moai have torsos.

And they have very long,
thin arms and hands.

They're huge statues,
and they're buried up to

their necks, literally,
in sediment and debris.

HUNT:
The moai have details
on the body.

Some have petroglyphs
on the body.

And people are
really fascinated by this,

because the common misperception
of the moai

comes from the really

iconic photos
of the heads alone.

So, people see that
and they just call them heads,

but it's correct to really
refer to the moai as statues.

SHATNER:
The discovery of
the full-sized moai statues

only deepens the mystery
surrounding them.

The revelation that some
of these monoliths are more than

twice as big
as previously believed

naturally begs the question,

how did the Rapa Nui move
the massive stones into place?

The transport
of these giant statues

has been a continuing mystery.

For example, the largest
moai ever transported

goes by the name of Paro.

Paro is about 33 feet tall,

and he's estimated to weigh
about 75 to 80 tons.

Paro was transported from
the quarry to the platform

where he was displayed,
and it's over three miles.

So, it's
an amazing accomplishment.

BARNHART:
The mystery of how
they moved these giant statues

has been a perennial question.

When the first
Europeans showed up and

asked the local people
how they did it,

they said, "Well, the statues
walked there themselves.

"They walked from
the quarry to these platforms

they stand on called ahu."

And so if we listen
to the Rapa Nui,

there was a magical quality
to creating these moai.

SHATNER:
Is it possible that the moai
somehow walked into place?

Of course, it sounds impossible,

but according to tests conducted
by archaeologists in 2012,

there may be some truth
to this legend.

What we showed in experiments,

with a replica
of an actual moai,

is that the statues have
a lower center of gravity

that makes them lean forward.

And if you attach ropes
to the head

and rock the statue,

the pendulum effect takes over,

allowing it to fall forward,

and the statue actually walks.

BARNHART:
It turns out that it looks like,
in the end,

the Rapa Nui may well be right.
Maybe they did walk there.

SHATNER:
Were the moai statues moved
by an ingenious use of ropes?

It's just one of the many
intriguing theories

about these giant stone statues.

But ultimately,
how they were transported

and became buried
up to their necks

remains unknown.

The moai of Easter Island really
have come to represent mystery.

Huge stone sculptures

on a grassy, windswept island--

people wonder
who made these and why.

And so the mystery continues.

SHATNER:
The revelation that some of
the buried moai of Easter Island

had full-sized bodies adds
a new wrinkle to the theories

about why they were designed
in the first place.

Perhaps it's when we dig deeper
into the Earth

that the true stories
from the ancient past

are finally revealed.

Like in the case
of an ancient complex

in the heart of North America,

where a deadly ritual
may have led to the demise

of an entire civilization.

SHATNER: In the heart
of the downtown district

stands the Wainwright Building.

Built in 1891,
this office building

is one of the world's
first modern skyscrapers.

But as it turns out,

there is a similarly sized
structure in this region

that is much, much older.

Just ten miles east of the city

stand the ruins of an ancient,
man-made pyramid mound

that was built centuries ago

and is as tall
as a ten-story building.

This is the largest
prehistoric earthwork

in the western hemisphere,

the largest totally earthen
mound built by ancient people

in North or South America.

Its base, actually, is bigger
than the Great Pyramid in Egypt

and it stands 100 feet high.

And it was built
with about 22 million

cubic feet of dirt
that had to be

carried in baskets on
people's backs and deposited.

SHATNER:
The fact that the ruins
of a man-made pyramid

sit in the middle
of the United States

might come as a surprise
for some.

And yet this monumental
earthen mound is merely one

of more than a hundred
similar structures

that have been discovered
in this area.

They are all part of a sprawling
ancient city

named Cahokia.

Cahokia is arguably
the most important

of the ancient cities
of North America.

Constructed approximately
between 700 and 1350 AD,

it was an incredible metropolis.

We have this idea
of the first peoples

as being hunter-gatherers

and riding around
on horses all the time,

and that's simply
the wrong impression.

They were
an incredibly technologically

sophisticated society.

ISEMINGER:
We don't know what
this place was called

or what the language
the people spoke here.

The name Cahokia
comes from a later group

of American Indians that moved
into this area in the 1600s

from further north,
around the Great Lakes.

They were here, but
they did not build the mounds.

They just later used it
as part of their settlement.

We often use the term "city"
when we talk about Cahokia

because of its magnitude.

It covered nearly six square
miles, or about 4,000 acres.

During its peak,
between 1050 and 1150 AD,

there were probably,
you know, 40, 50,000 people

living within this region.

It would be larger
than London was at that time.

And yet, 200 years later,

by 1350 AD,

the whole place
had been abandoned.

And indeed, there is a mystery

of exactly
what took place there.

SHATNER:
But if Cahokia was
such a thriving metropolis,

then it begs the question--

how did this civilization
come to an end?

It's a mystery that has
driven archaeologists

to scour Cahokia's ruins
in search of an answer.

There are a number of hypotheses
about the decline of Cahokia.

One involves evidence
of a defensive wall

that was built around
the center of Cahokia.

So, that indicates that they had
conflicts and warfare.

And there's been suggestions
that maybe,

with the crowded
conditions here,

perhaps there was
increases in disease.

SHATNER:
Did the threat of warfare
or poor living conditions

cause the inhabitants
of Cahokia

to abandon this thriving city?

It's hard to say.

But in recent years,
another theory has emerged.

One that suggests there may
have been a more sinister reason

behind Cahokia's demise.

So, one of the ideas
that's been put forward is

that something quite dark
took place there,

and this is why there's little
evidence in the oral tradition

or the folklore of this area.

And this could be, ultimately,
why the site was abandoned.

ISEMINGER:
Back in the late '60s and early
'70s, there was an excavation

at a small mound here
on the site called Mound 72.

As we dug further
into the mound,

there was a burial pit
about five feet deep.

And at the bottom of that
they found

53 mostly young women,

all buried at the same time,

laid out in two rows
and piled in there two-deep.

Next to them were four men

with their heads
and their hands cut off,

apparently in some ritual.

The burials that
came out of Mound 72

quite clearly showed evidence
of mass sacrifice.

We have to ask ourselves

whether this would
have had any kind of impact

upon the society
as a whole at Cahokia.

SHATNER:
Did the vast majority
of Cahokia's inhabitants

abandon their city

because its leaders were
engaging in the practice

of human sacrifice?

And if so,
then where did they go?

Is this tragedy
enough to explain

why there is no written record

that this civilization
ever existed?

For now, experts
remain collectively baffled

and worry that
we may never know for sure.

We really must question,
you know,

what really happened, because

it could have been something
much more mysterious

that we just don't know about.

SHATNER:
Just off the coast
of Alexandria,

in the Abu Qir Bay...

...a team
of underwater archaeologists

begin the hunt for a lost
Egyptian city known as Thonis.

CHRIS NAUNTON:
Thonis was known

in only the sort of
sparsest detail thanks to a few

ancient sources
in which it's mentioned,

but it had for a very
long time

not been identified
archaeologically.

So we knew it must have
existed because text

told us so, we just
had no idea where it was.

SHATNER:
Then, in the year 2000,

at a depth of some 30 feet,

divers found
ancient Egyptian statues,

hoards of gold
coins and jewelry, and even

the ruins
of buildings and roads.

All part of
the massive city of Thonis,

that was rediscovered at last.

One of the most
amazing discoveries made

was the temple of Amun.

And this temple
was absolutely vast,

constructed of these
incredibly big stone blocks.

So, we have a really
visceral idea of the size

and the monumentality
of this temple.

We also have an enormous,
colossal statue

of the god Hapi,

who's a kind of personification
of the Nile.

It's appropriate that
you would have a god like this

present at the sort of entrance,

if you like,
the Mediterranean entrance

to the Nile delta region
and the Nile River itself.

SHATNER:
Thousands of artifacts
have been recovered from Thonis,

and archaeologists estimate
that it was three times

the size of the ancient
Roman city of Pompeii.

But how did this vast,
remarkable city

sink beneath the waves?

BRADSHAW:
What we think
happened with Thonis is

an earthquake in around
the second century BC

caused the city
to sink into the water.

And Thonis was lost to history.

But we've really only
scratched the surface

in terms of what
we know about the city.

A huge mystery still remains.

And in large part, that's
because 95% of the city

remains underwater and remains
in need of investigation.

Only five percent
seems to have been discovered.

So, the questions remain.

SHATNER:
While the full excavation
of Thonis will take decades...

...archaeologists and explorers
continue to scour the globe

in search of other lost cities

that capture
people's imaginations.

The reason why people
look for lost cities like

Xanadu or Petra
or anywhere else

is because we want to be

the next discoverers of this

incredible lost realm that
nobody has set their eyes on,

perhaps for thousands of years.

Because you just
don't know exactly what

you're gonna discover.

It's exciting to think about
what future

archeological finds will reveal.

Perhaps an artifact
from Atlantis

will be found deep underwater.

Or the discovery of other
islands like Nan Madol

will prove that
the continent of Mu

once towered above
the ocean waves.

And as technology evolves,
lost civilizations

might be spotted without
ever having to raise a shovel.

With every new revelation,
we get one step closer

to understanding
how our ancestors once lived.

But for now, the true history
of our ancient past

will remain unexplained.

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